黄土区大跨度隧道开挖技术探讨

Exploration of Excavation Technology for Large-span Tunnels in Loess Areas

临洮(安家咀)至临夏一级公路百和隧道均为Ⅴ级围岩,主要有黄土浅埋段、岩质地段、黄土深埋段、小净距段以及黄土深埋段等情况,针对不同的围岩情况和地质条件,有针对性的采用CD法、上下台阶留核心土法及三台阶分步法进行开挖。

Baihe Tunnel of Lintao(Anjiazui)-Linxia first-class highway is Grade V surrounding rock,mainly including loess shallow buried section,rocky section,loess deep buried section,small clearance section and loess deep buried section.According to different surrounding rock conditions and geological conditions,CD method,upper and lower benches retaining core soil method and three bench step-by-step method are targeted for excavation.